html {
  scroll-behavior: smooth;
}

* {
  box-sizing: border-box;
  font-family: 'SVN-Avo', 'Arial', sans-serif !important;
}

/* Biến toàn bộ body thành màu Xanh rêu siêu đậm */
body {
  margin: 0;
  padding: 0;
  background-color: #021a17; /* Đen pha ánh rêu */
  color: #e0e0e0; /* Chữ mặc định sang màu sáng */
  overflow-x: hidden;
}

/* ================= HEADER (Biến thành kính mờ) ================= */
.main-header {
  background-color: rgba(2, 26, 23, 0.75); /* Nền trong suốt */
  backdrop-filter: blur(15px); /* Hiệu ứng kính */
  -webkit-backdrop-filter: blur(15px);
  width: 100%;
  position: sticky;
  top: 0;
  z-index: 1000;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05); /* Viền kính hắt sáng nhẹ */
}

.header-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
  padding: 15px 20px;
}
/* Kích thước của ảnh Logo */
.dt-logo-img {
  max-height: 45px; /* Chiều cao tối đa của logo, bạn có thể tăng giảm số 45 này cho vừa mắt */
  width: auto;
  display: block;
  transition: transform 0.3s ease;
}

/* Nảy nhẹ logo lên khi rê chuột vào cho thêm phần sinh động */
.dt-logo-img:hover {
  transform: scale(1.05);
}
.header-logo .logo-text {
  color: #ffb800; /* Logo màu vàng cam cực kỳ nổi bật trên nền tối */
  font-size: 28px;
  font-weight: 900;
  letter-spacing: 1px;
}

.header-nav ul {
  display: flex;
  list-style: none;
  gap: 25px;
  margin: 0;
  padding: 0;
}

.header-nav a {
  text-decoration: none;
  color: #e0e0e0; /* Link màu sáng */
  font-weight: 700;
  font-size: 15px;
  transition: color 0.3s ease;
}

.header-nav a:hover {
  color: #ffb800;
}

.btn-header {
  background-color: #0b7a6d;
  color: #ffffff !important;
  text-decoration: none;
  padding: 12px 25px;
  border-radius: 30px;
  font-weight: 700;
  font-size: 14px;
  transition: opacity 0.3s ease;
}

.btn-header:hover {
  opacity: 0.85;
}

/* ================= CÁC ĐỐM SÁNG (GLOW) TẠO HIỆU ỨNG ================= */
.dt-glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(90px);
  z-index: -1;
  pointer-events: none; /* Không cản trở click chuột */
}
.dt-glow-1 { width: 400px; height: 400px; background: #0b7a6d; top: -50px; left: 10%; opacity: 0.6; }
.dt-glow-2 { width: 500px; height: 500px; background: #ffb800; bottom: -150px; right: 5%; opacity: 0.3; }
.dt-glow-3 { width: 600px; height: 600px; background: #0b7a6d; top: 50%; left: 50%; transform: translate(-50%, -50%); opacity: 0.2; }
.dt-glow-4 { width: 500px; height: 500px; background: #ffb800; top: 30%; left: 50%; transform: translate(-50%, -50%); opacity: 0.15; }


/* ================= HERO SECTION ================= */
.dt-hero-section-full {
  position: relative;
  width: 100vw; 
  left: 50%;
  right: 50%;
  margin-left: -50vw;
  margin-right: -50vw;
  padding: 80px 20px 120px 20px;
  z-index: 1;
}

.dt-glass-panel {
  background: rgba(255, 255, 255, 0.03);
  backdrop-filter: blur(25px);
  -webkit-backdrop-filter: blur(25px);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 30px;
  padding: 60px 50px;
  box-shadow: 0 30px 60px rgba(0, 0, 0, 0.5);
}

.dt-hero-grid { display: grid; grid-template-columns: 1.2fr 1fr; gap: 50px; align-items: center; }

.dt-hero-subtitle { color: #a5d6d1; font-size: 16px; text-transform: uppercase; letter-spacing: 2px; margin-bottom: 15px; display: inline-block;}
.dt-hero-title { font-size: 48px; font-weight: 900; line-height: 1.2; color: #ffffff; margin: 0 0 15px 0; }
.dt-highlight { color: #ffb800; text-shadow: 0 0 20px rgba(255, 184, 0, 0.3); }
.dt-hero-desc { font-size: 20px; font-weight: 700; color: rgba(255, 255, 255, 0.9); margin-bottom: 30px; }

.dt-hero-features { list-style: none; padding: 0; margin: 0 0 40px 0; }
.dt-hero-features li { position: relative; padding-left: 35px; margin-bottom: 15px; font-size: 16px; color: rgba(255, 255, 255, 0.8); }
.dt-hero-features li::before {
  content: '✔'; position: absolute; left: 0; top: -2px;
  background-color: #ffb800; color: #333; width: 24px; height: 24px;
  display: flex; align-items: center; justify-content: center;
  border-radius: 50%; font-size: 12px; font-weight: bold;
}

.dt-hero-img { width: 100%; max-width: 550px; height: auto; object-fit: contain; display: block; margin: 0 auto; animation: dt-float-img 4s ease-in-out infinite; }
@keyframes dt-float-img { 0% { transform: translateY(0px); } 50% { transform: translateY(-20px); } 100% { transform: translateY(0px); } }

@media (max-width: 992px) {
  .dt-hero-grid { grid-template-columns: 1fr; }
  .dt-glass-panel { padding: 40px 30px; }
  .dt-hero-title { font-size: 36px; }
}

/* ================= LỢI ÍCH KHÓA HỌC (GLASS) ================= */
.dt-benefits-section { position: relative; padding: 80px 20px 100px 20px; width: 100%; z-index: 2; }
.dt-benefits-header { text-align: center; margin-bottom: 50px; }
.dt-section-title { font-size: 36px; font-weight: 900; color: #ffffff; margin: 0 0 15px 0;}
.dt-section-subtitle { font-size: 16px; color: rgba(255,255,255,0.7); max-width: 700px; margin: 0 auto; line-height: 1.6;}

.dt-benefits-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }

/* Biến thẻ thành kính mờ */
.dt-benefit-card {
  background: rgba(255, 255, 255, 0.03);
  backdrop-filter: blur(15px);
  -webkit-backdrop-filter: blur(15px);
  padding: 40px 30px;
  border-radius: 20px;
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-bottom: 4px solid #0b7a6d; 
  text-align: center;
  transition: transform 0.3s ease, box-shadow 0.3s ease, background 0.3s ease;
}

.dt-benefit-card:hover {
  transform: translateY(-10px);
  background: rgba(255, 255, 255, 0.06);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
}

.dt-benefit-icon { font-size: 50px; margin-bottom: 20px; line-height: 1; }
.dt-benefit-tag { font-size: 13px; font-weight: 700; color: #ffb800; text-transform: uppercase; letter-spacing: 1px; display: block; margin-bottom: 12px; }
.dt-benefit-heading { font-size: 22px; font-weight: 800; color: #ffffff; margin: 0 0 15px 0; }
.dt-benefit-desc { font-size: 15px; color: rgba(255,255,255,0.7); line-height: 1.6; margin: 0; }

@media (max-width: 992px) { .dt-benefits-grid { grid-template-columns: 1fr; max-width: 500px; margin: 0 auto; } }

/* ================= CHI TIẾT KHÓA HỌC (ZIG-ZAG) ================= */
.dt-courses-detail-section { padding: 60px 20px; width: 100%; position: relative; z-index: 2;}
.dt-container { max-width: 1200px; margin: 0 auto; }

.dt-course-row { display: flex; align-items: center; justify-content: space-between; gap: 60px; margin-bottom: 100px; }
.dt-course-row.dt-reverse { flex-direction: row-reverse; }

.dt-course-visual { flex: 1; width: 100%; }

/* Khung ảnh mockup thành kính mờ phát sáng nhẹ */
.dt-mockup-box {
  width: 100%; height: 400px;
  background: rgba(11, 122, 109, 0.1);
  backdrop-filter: blur(10px);
  border-radius: 24px;
  display: flex; align-items: center; justify-content: center;
  color: #ffb800; font-weight: bold; font-size: 20px;
  border: 1px solid rgba(11, 122, 109, 0.3);
  box-shadow: inset 0 0 30px rgba(11, 122, 109, 0.1);
  transition: transform 0.3s ease;
}
.dt-course-row:hover .dt-mockup-box { transform: scale(1.02); background: rgba(11, 122, 109, 0.15); }

.dt-course-content { flex: 1; }
.dt-course-tag { display: inline-block; background-color: rgba(11, 122, 109, 0.2); color: #a5d6d1; padding: 6px 15px; border-radius: 20px; font-size: 14px; font-weight: 700; margin-bottom: 15px; text-transform: uppercase; border: 1px solid rgba(11, 122, 109, 0.4);}
.dt-course-heading { color: #ffffff; font-size: 40px; font-weight: 900; margin: 0 0 20px 0; line-height: 1.2; }
.dt-course-desc { color: rgba(255,255,255,0.75); font-size: 16px; line-height: 1.7; margin: 0 0 20px 0; }

.dt-course-benefits { list-style: none; padding: 0; margin: 0 0 35px 0; }
.dt-course-benefits li { position: relative; padding-left: 25px; margin-bottom: 12px; color: rgba(255,255,255,0.85); font-size: 16px; }
.dt-course-benefits li::before { content: '✓'; position: absolute; left: 0; color: #ffb800; font-weight: bold; }

.dt-btn-primary {
  display: inline-block; background-color: #0b7a6d; color: #ffffff !important;
  text-decoration: none; padding: 14px 35px; border-radius: 30px; font-weight: 700; font-size: 16px;
  transition: all 0.3s ease; box-shadow: 0 8px 20px rgba(11, 122, 109, 0.3);
}
.dt-btn-primary:hover { background-color: #085e54; transform: translateY(-2px); box-shadow: 0 12px 25px rgba(11, 122, 109, 0.5); }

@media (max-width: 992px) {
  .dt-course-row, .dt-course-row.dt-reverse { flex-direction: column; gap: 30px; margin-bottom: 70px; }
  .dt-course-content { text-align: center; }
  .dt-course-benefits li { text-align: left; display: inline-block; }
}

/* ================= BẢNG GIÁ (GLASS) ================= */
.dt-pricing-section { position: relative; padding: 100px 20px; z-index: 2;}

.dt-pricing-title-wrapper { text-align: center; margin-bottom: 60px; width: 100%; }
.dt-pricing-title-box {
  display: inline-block; padding: 15px 50px;
  background: rgba(255, 255, 255, 0.05); backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.1); border-radius: 50px;
}
.dt-pricing-main-title { color: #ffffff; font-size: 32px; font-weight: 900; margin: 0 0 8px 0; text-transform: uppercase; }
.dt-pricing-sub-title { color: rgba(255,255,255,0.7); font-size: 16px; margin: 0; }

.dt-pricing-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; margin-top: 50px; }

/* Bảng giá thường */
.dt-price-card {
  background: rgba(255, 255, 255, 0.03); backdrop-filter: blur(15px);
  padding: 50px 30px; border-radius: 20px; text-align: center; position: relative;
  transition: all 0.3s ease; border: 1px solid rgba(255, 255, 255, 0.1);
  display: flex; flex-direction: column; height: 100%; 
}

/* Bảng giá nổi bật */
.dt-price-card.dt-featured {
  background: rgba(11, 122, 109, 0.3); border: 1px solid rgba(255, 184, 0, 0.4);
  transform: scale(1.05); z-index: 2; box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
}

.dt-featured-label { position: absolute; top: 0; left: 50%; transform: translate(-50%, -50%); background: #ffb800; color: #333; padding: 8px 20px; border-radius: 20px; font-weight: 800; font-size: 12px; }
.dt-price-header h3 { font-size: 20px; margin-bottom: 20px; color: #ffffff;}
.dt-price-value { font-size: 40px; font-weight: 900; margin-bottom: 30px; color: #ffffff;}
.dt-price-value span { font-size: 20px; text-decoration: underline; }
.dt-featured .dt-price-value { color: #ffb800; }

.dt-price-features { list-style: none; padding: 0; margin: 0 0 40px 0; text-align: left; flex-grow: 1; }
.dt-price-features li { margin-bottom: 15px; padding-left: 25px; position: relative; color: rgba(255,255,255,0.8);}
.dt-price-features li::before { content: '✔'; position: absolute; left: 0; color: #0b7a6d; }
.dt-featured .dt-price-features li::before { color: #ffb800; }

.dt-btn-price { display: block; padding: 15px; border: 1px solid rgba(255,255,255,0.3); border-radius: 30px; color: #ffffff; text-decoration: none; font-weight: 800; transition: all 0.3s ease; }
.dt-btn-price:hover { background: rgba(255,255,255,0.1); border-color: #ffffff; }

.featured-btn { background: #ffb800; border-color: #ffb800; color: #333 !important; }
.featured-btn:hover { background: #e6a600; border-color: #e6a600; }

@media (max-width: 992px) { .dt-pricing-grid { grid-template-columns: 1fr; max-width: 400px; margin: 50px auto 0; } .dt-price-card.dt-featured { transform: scale(1); margin: 40px 0; } }

/* Ghi chú bảng giá Premium Glass */
.dt-pricing-note-premium {
  display: flex; justify-content: space-between; gap: 25px; margin-top: 60px; padding: 35px;
  background: rgba(255, 255, 255, 0.03); backdrop-filter: blur(15px);
  border-radius: 16px; border: 1px solid rgba(255, 255, 255, 0.08);
}
.dt-note-item { display: flex; align-items: flex-start; gap: 15px; flex: 1; }
.dt-note-icon { font-size: 22px; background: rgba(255,255,255,0.05); color: #a5d6d1; width: 48px; height: 48px; display: flex; align-items: center; justify-content: center; border-radius: 50%; flex-shrink: 0; transition: transform 0.3s ease; border: 1px solid rgba(255,255,255,0.1);}
.dt-note-item:hover .dt-note-icon { transform: translateY(-3px); }
.dt-note-item.highlight .dt-note-icon { background: rgba(255, 184, 0, 0.15); color: #ffb800; border-color: rgba(255,184,0,0.3); }

.dt-note-text { font-size: 14px; color: rgba(255,255,255,0.7); line-height: 1.5; }
.dt-note-text strong { display: block; color: #ffffff; margin-bottom: 6px; font-size: 16px; font-weight: 800; }
.dt-note-item.highlight .dt-note-text strong { color: #ffb800; }
@media (max-width: 900px) { .dt-pricing-note-premium { flex-direction: column; gap: 30px; } }

/* ================= QUY TRÌNH (GLASS) ================= */
.dt-process-section { padding: 100px 20px; width: 100%; position: relative; z-index: 2;}
.dt-process-section .dt-section-header { text-align: center; margin-bottom: 60px; }

.dt-process-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; }

.dt-process-card {
  background: rgba(255, 255, 255, 0.02); backdrop-filter: blur(10px);
  padding: 40px 30px; border-radius: 20px; text-align: left; position: relative;
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275); 
  border: 1px solid rgba(255, 255, 255, 0.05); overflow: hidden; display: flex; flex-direction: column; height: 100%;
}

.dt-process-card:hover {
  transform: translateY(-15px);
  background: rgba(11, 122, 109, 0.3); border-color: rgba(11, 122, 109, 0.8);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
}

.dt-step-title { color: #a5d6d1; font-size: 22px; font-weight: 800; margin: 0 0 15px 0; position: relative; z-index: 2; transition: color 0.3s ease; }
.dt-step-desc { color: rgba(255,255,255,0.6); font-size: 15px; line-height: 1.6; margin: 0; position: relative; z-index: 2; transition: color 0.3s ease; }

.dt-process-card:hover .dt-step-title, .dt-process-card:hover .dt-step-desc { color: #ffffff; }

.dt-step-number {
  font-size: 120px; font-weight: 900; color: rgba(255, 255, 255, 0.03); 
  position: absolute; bottom: -20px; right: 10px; line-height: 1; transition: color 0.4s ease; z-index: 1; 
}
.dt-process-card:hover .dt-step-number { color: rgba(255, 184, 0, 0.1); }

@media (max-width: 1024px) { .dt-process-grid { grid-template-columns: repeat(2, 1fr); gap: 20px; } }
@media (max-width: 576px) { .dt-process-grid { grid-template-columns: 1fr; } }


/* ================= FORM LIÊN HỆ & POPUP (GLASS) ================= */
.dt-contact-section { padding: 80px 20px; position: relative; z-index: 2;}
.dt-contact-wrapper {
  max-width: 900px; margin: 0 auto;
  background: rgba(11, 122, 109, 0.15); backdrop-filter: blur(25px); -webkit-backdrop-filter: blur(25px);
  border-radius: 24px; padding: 60px 50px; text-align: center; color: #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: 0 30px 60px rgba(0, 0, 0, 0.6);
}

.dt-contact-badge { display: inline-block; background: rgba(255, 255, 255, 0.1); padding: 8px 25px; border-radius: 30px; font-size: 13px; font-weight: 700; letter-spacing: 1px; margin-bottom: 20px; border: 1px solid rgba(255,255,255,0.1);}
.dt-contact-title { font-size: 32px; font-weight: 900; margin: 0 0 10px 0; }
.dt-contact-subtitle { font-size: 16px; color: rgba(255,255,255,0.8); margin-bottom: 40px; }

.dt-form-row { display: flex; gap: 15px; margin-bottom: 15px; }
.dt-col-12 { flex: 0 0 100%; } .dt-col-6 { flex: 0 0 calc(50% - 7.5px); } .dt-col-3 { flex: 0 0 calc(25% - 11.25px); }

/* Chỉnh Input sang chế độ Dark Glass */
.dt-input {
  width: 100%; padding: 16px 20px; border-radius: 8px; font-size: 15px; font-family: inherit;
  background: rgba(255, 255, 255, 0.05); color: #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.15); outline: none; transition: all 0.3s ease;
}
.dt-input::placeholder { color: rgba(255, 255, 255, 0.4); }
.dt-input:focus { background: rgba(255, 255, 255, 0.1); border-color: #ffb800; box-shadow: 0 0 0 3px rgba(255, 184, 0, 0.3); }

/* Mẹo để menu xổ xuống (Option) không bị xấu trên nền tối */
select.dt-input option { background: #02201c; color: #ffffff; }

select.dt-input {
  cursor: pointer; appearance: none;
  background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='rgba(255,255,255,0.6)' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
  background-repeat: no-repeat; background-position: right 15px center; background-size: 16px;
}
textarea.dt-input { resize: none; }
.dt-form-submit { margin-top: 30px; }

.dt-btn-submit { background-color: #ffb800; color: #333333; border: none; padding: 16px 50px; border-radius: 30px; font-size: 16px; font-weight: 800; cursor: pointer; transition: all 0.3s ease; box-shadow: 0 8px 20px rgba(255, 184, 0, 0.2); }
.dt-btn-submit:hover { transform: translateY(-3px); background-color: #e6a600; box-shadow: 0 12px 25px rgba(255, 184, 0, 0.4); }

/* --- POPUP MODAL (GLASS) --- */
.dt-modal-overlay { display: none; position: fixed; top: 0; left: 0; width: 100%; height: 100%; background-color: rgba(0, 0, 0, 0.8); z-index: 9999; justify-content: center; align-items: center; padding: 20px; }
.dt-modal-content {
  background: rgba(11, 122, 109, 0.25); backdrop-filter: blur(35px); -webkit-backdrop-filter: blur(35px);
  width: 100%; max-width: 600px; padding: 50px 40px; border-radius: 20px; position: relative; text-align: center; color: #ffffff;
  border: 1px solid rgba(255,255,255,0.15); box-shadow: 0 30px 80px rgba(0,0,0,0.8);
  animation: modalFadeIn 0.3s ease;
}
@keyframes modalFadeIn { from { opacity: 0; transform: translateY(-20px); } to { opacity: 1; transform: translateY(0); } }
.dt-modal-close { position: absolute; top: 15px; right: 25px; font-size: 32px; font-weight: bold; color: rgba(255,255,255,0.5); cursor: pointer; transition: color 0.3s ease; }
.dt-modal-close:hover { color: #ffffff; }

@media (max-width: 768px) {
  .dt-form-row { flex-direction: column; gap: 15px; }
  .dt-col-6, .dt-col-3 { flex: 0 0 100%; }
  .dt-contact-wrapper, .dt-modal-content { padding: 40px 20px; }
  .dt-contact-title { font-size: 24px; }
}

/* ================= FOOTER ================= */
.dt-footer { background-color: #010a09; color: #ffffff; padding: 80px 20px 20px 20px; border-top: 1px solid rgba(255,255,255,0.05); position: relative; z-index: 2;}
.dt-footer-grid { display: grid; grid-template-columns: 2fr 1.5fr 1fr; gap: 50px; margin-bottom: 60px; }
.dt-footer-logo { color: #ffb800; font-size: 28px; font-weight: 900; margin: 0 0 20px 0; letter-spacing: 1px; }
.dt-footer-desc { font-size: 15px; line-height: 1.6; color: rgba(255, 255, 255, 0.6); max-width: 400px; }
.dt-footer-heading { font-size: 18px; font-weight: 700; margin: 0 0 25px 0; color: #ffffff; text-transform: uppercase; }
.dt-footer-contact { list-style: none; padding: 0; margin: 0; }
.dt-footer-contact li { font-size: 14px; line-height: 1.5; color: rgba(255, 255, 255, 0.6); margin-bottom: 15px; }
.dt-footer-links { list-style: none; padding: 0; margin: 0; }
.dt-footer-links li { margin-bottom: 12px; }
.dt-footer-links a { color: rgba(255, 255, 255, 0.6); text-decoration: none; font-size: 15px; transition: color 0.3s ease; }
.dt-footer-links a:hover { color: #ffb800; }
.dt-footer-bottom { border-top: 1px solid rgba(255, 255, 255, 0.05); padding-top: 20px; text-align: center; font-size: 14px; color: rgba(255, 255, 255, 0.3); }

@media (max-width: 900px) { .dt-footer-grid { grid-template-columns: 1fr; gap: 40px; } }

/* ================= ICON TRÔI NỔI ================= */
.dt-floating-contact { position: fixed; bottom: 40px; right: 30px; display: flex; flex-direction: column; gap: 20px; z-index: 9999; }
.dt-float-btn {
  position: relative; width: 55px; height: 55px; border-radius: 50%; display: flex; justify-content: center; align-items: center;
  text-decoration: none; background-color: #ffffff; box-shadow: 0 4px 15px rgba(0,0,0,0.5); transition: transform 0.3s ease;
}
.dt-float-btn:hover { transform: scale(1.1); }
.dt-float-btn img { width: 35px; height: 35px; object-fit: contain; z-index: 2; }
.dt-phone-icon { font-size: 26px; z-index: 2; color: #ffffff; }
.dt-phone { background-color: #0b7a6d; border: 2px solid rgba(255,255,255,0.2);}

.dt-animated-ring { position: absolute; width: 100%; height: 100%; border-radius: 50%; z-index: 1; animation: dt-ripple 1.5s infinite ease-out; }
.dt-zalo .dt-animated-ring { background-color: #0068ff; } .dt-mess .dt-animated-ring { background-color: #00c6ff; } .dt-phone .dt-animated-ring { background-color: #0b7a6d; }
@keyframes dt-ripple { 0% { transform: scale(1); opacity: 0.7; } 100% { transform: scale(1.8); opacity: 0; } }

.dt-phone .dt-phone-icon { animation: dt-tada 1.5s infinite; }
@keyframes dt-tada {
  0% { transform: scale(1); }
  10%, 20% { transform: scale(0.9) rotate(-8deg); }
  30%, 50%, 70%, 90% { transform: scale(1.1) rotate(8deg); }
  40%, 60%, 80% { transform: scale(1.1) rotate(-8deg); }
  100% { transform: scale(1) rotate(0); }
}

@media (max-width: 768px) { .dt-floating-contact { bottom: 20px; right: 20px; gap: 15px; } .dt-float-btn { width: 45px; height: 45px; } .dt-float-btn img { width: 28px; height: 28px; } .dt-phone-icon { font-size: 20px; } }
/* style.css - Dán vào CUỐI CÙNG của file */

/* 1. Xóa style của chữ Dương Tùng cũ ở footer */
.dt-footer-col h3.dt-footer-logo {
    display: none !important;
}

/* 2. Style cho cái khung bọc logo mới để nó nằm gọn trong cột 1 */
.dt-footer-logo-wrap {
    display: block;
    width: 100%;
    margin-bottom: 25px; /* Tạo khoảng trống phía dưới logo */
    text-align: left; /* Logo nằm canh trái trong cột footer */
}

/* 3. Style kích thước cho ảnh Logo Footer */
.dt-logo-footer-img {
    /* Cho logo footer to hơn header một chút cho sang */
    max-height: 90px; 
    width: auto;
    display: block;
    margin: 0; /* Đảm bảo không bị căn giữa */
}
/* Style cho ảnh thật của các khóa học (thay thế mockup) */
.dt-course-img {
    width: 100%;
    height: auto;
    border-radius: 24px; 
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4); 
    border: 1px solid rgba(255, 255, 255, 0.1); 
    transition: transform 0.3s ease;
}

/* Hiệu ứng phóng to nhẹ ảnh khi rê chuột vào */
.dt-course-row:hover .dt-course-img {
    transform: scale(1.02);
}